The second Gordon Research Conference on calcium oxalate has been approved for June 12-16, 1989, and will be held at Plymouth State College, Plymouth, New Hampshire. The conference will focus on physical, chemical and biological research on calcium oxalate. The importance of research on calcium oxalate in man and other vertebrates evolves from the fact that ten percent of the human population experiences urolithiasis. Until an inexpensive prophylaxis of calcium oxalate urolithiasis is developed, there will continue to be a serious need for intensive research centering on calcium oxalate. Calcium oxalate produced by bacteria, plants and fungi contribute to the urolithiasis problem through diet. However, studies of calcium oxalate in these organisms offer model systems and unique opportunities that will stimulate investigators studying human urolithiasis. The second Gordon Conference of Calcium Oxalate also will extend the interdisciplinary ties and understanding among a diverse group of researchers who do not normally meet together. The major focus of this conference will be to develop and enunciate the areas of fruitful research, both near and long term, that should directly benefit mankind though the development of greater understanding of calcium oxalate in urolithiasis.